fix(webapp): don't re-toast a watch wake another browser already read

The poll deduped fresh wakes against a 50-id localStorage set alone, so inside
the feed's 15-minute window a second browser — or one whose site data was
cleared — toasted wakes the user had already read. The payload's own `unread`
flag now gates the toast as well. A wake landing in an open chat stays unread
until that chat's next read, so it still toasts.

Author: kathiekiwi

apps/webapp/app/components/dashboard-agent/DashboardAgent.tsx

@@ -23,7 +23,7 @@ import {
 } from "./panel-layout";
 import { nextPendingTurnChatId } from "./pending-turn";
 import { nextVisibleChat } from "./unread-counts";
-import { startWakePolling } from "./wake-poll";
+import { startWakePolling, wakesToToast } from "./wake-poll";
 import { shouldPollWakeFeed, subscribeWatchActivity } from "./watch-activity";
 import {
   showWatchWakesSummaryToast,
@@ -217,7 +217,7 @@ export function DashboardAgent({
         // A chat open in the panel is being read right now, so it isn't unread work.
         setUnreadWork(Math.max(0, (data.unreadWork ?? 0) - (open && visibleChat.current ? 1 : 0)));
 
-        const fresh = (data.wakes ?? []).filter((wake) => !toastedWakes.current.has(wake.watchId));
+        const fresh = wakesToToast(data.wakes, toastedWakes.current);
         for (const wake of fresh) rememberToasted(wake.watchId);
 
         if (fresh.length > WAKE_TOAST_MAX_INDIVIDUAL) {

apps/webapp/app/components/dashboard-agent/wake-poll.test.ts

@@ -1,5 +1,5 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
-import { startWakePolling, UNREAD_POLL_INTERVAL_MS } from "./wake-poll";
+import { startWakePolling, UNREAD_POLL_INTERVAL_MS, wakesToToast } from "./wake-poll";
 
 function harness() {
   let hidden = false;
@@ -98,3 +98,29 @@ describe("startWakePolling", () => {
     expect(vi.getTimerCount()).toBe(0);
   });
 });
+
+describe("wakesToToast", () => {
+  const wake = (watchId: string, unread: boolean) => ({ watchId, unread });
+
+  it("skips a wake another machine already read, and keeps the unread one", () => {
+    const wakes = [wake("watch_read", false), wake("watch_new", true)];
+
+    expect(wakesToToast(wakes, new Set())).toEqual([wake("watch_new", true)]);
+  });
+
+  it("still skips what this browser toasted, read or not", () => {
+    const wakes = [wake("watch_seen", true), wake("watch_new", true)];
+
+    expect(wakesToToast(wakes, new Set(["watch_seen"]))).toEqual([wake("watch_new", true)]);
+  });
+
+  // The read POST is what clears it, and that only runs once the chat is looked at.
+  it("toasts a wake that landed in an open chat, because it is still unread", () => {
+    expect(wakesToToast([wake("watch_in_view", true)], new Set())).toHaveLength(1);
+  });
+
+  it("treats a wake with no unread flag as already seen rather than guessing", () => {
+    expect(wakesToToast([{ watchId: "watch_old" }], new Set())).toEqual([]);
+    expect(wakesToToast(undefined, new Set())).toEqual([]);
+  });
+});

apps/webapp/app/components/dashboard-agent/wake-poll.ts

@@ -8,6 +8,19 @@ export const UNREAD_POLL_INTERVAL_MS = 60_000;
 // Added to each delay so open tabs never settle into polling on the same second.
 export const UNREAD_POLL_JITTER_MS = 15_000;
 
+/**
+ * Which of the feed's wakes this tab should toast. The feed is recent deliveries, not
+ * unread ones, and the local memory of what was toasted is per browser — so `unread` is the
+ * only signal shared across machines that a wake has already been seen. A wake landing in
+ * an open chat stays unread until that chat's next read, so it still toasts.
+ */
+export function wakesToToast<T extends { watchId: string; unread?: boolean }>(
+  wakes: T[] | undefined,
+  toasted: ReadonlySet<string>
+): T[] {
+  return (wakes ?? []).filter((wake) => wake.unread === true && !toasted.has(wake.watchId));
+}
+
 export type WakePollOptions = {
   load: () => Promise<void>;
   isHidden: () => boolean;